Physical Sciences and Mathematics | Open Access Articles

Particle Correlations At High Partonic Density, Kirill Tuchin

Kirill Tuchin

We discuss manifestations of the particle correlations at high partonic density in the heavy-ion collisions at RHIC. In particular, we argue that the elliptic flow variable v% is dominated by particle correlations at high PT

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Qcd In Curved Space-Time: A Conformal Bag Model, Dmitri Kharzeev, Eugene Levin, Kirill Tuchin

Kirill Tuchin

We construct an effective low energy Lagrangian using constraints imposed by the renormalization group. Degrees of freedom are gluons and a scalar glueball. This effective theory has a dual description as classical gluodynamics on a curved conformal background. Color fields are dynamically confined, and the strong coupling freezes at distances larger than the glueball size. We make specific predictions (in particular, on the Nc dependence of glueball properties) which can be tested in lattice simulations of gluodynamics.

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Magnetospheric Electric Fields And Plasma Sheet Injections To Low-Lshells During The June 4-5, 1991 Magnetic Storm: Comparison Between The Rice Convectionmodel And Observations, T. W. Garner, R. A. Wolf, R. W. Spiro, W. J. Burke, Bela G. Fejer, S. Sazykin, J. L. Roeder, M. R. Hairston

Bela G. Fejer

[1] The major magnetic storm of 4–5 June 1991 was well observed with the Combined Release and Radiation Experiment (CRRES) satellite in the duskside inner magnetosphere and with three Defense Meteorological Satellite Program (DMSP) spacecraft in the polar ionosphere. These observations are compared to results from the Rice Convection Model (RCM), which calculates the inner magnetospheric electric field and particle distribution self-consistently. This case study, which uses the most complete RCM runs to date, demonstrates two significant features of magnetospheric storms, the development of subauroral polarization streams (SAPS) and plasma-sheet particle injection deep into the inner magnetosphere. In particular, the …

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Nanoscale Electronics Based On 2d Dopant Patterns In Silicon, T. -C. Shen, J. S. Kline, T. Schenkel, S. J. Robinson, J. -Y. Ji, C. L. Yang, R. R. Du, J. R. Tucker

T. -C. Shen

A nanoscale fabrication process compatible with present Si technology is reported. Preimplanted contact arrays provide external leads for scanning tunneling microscope (STM)-defined dopantpatterns. The STM’s low energy electron beam removes hydrogen from H terminated Si(100) surfaces for selective adsorption of PH₃ precursor molecules, followed by room temperature Si overgrowth and 500 °C rapid thermal anneal to create activated P-donor patterns in contact with As⁺-implanted lines. Electrical and magnetoresistance measurements are reported here on 50 and 95 nm-wide P-donor lines, along with Ga-acceptor wires created by focused ion beams, as a means for extending Si device fabrication toward …

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Effects Of Counterion Fluctuations In A Polyelectrolyte Brush, Christian Santangelo, A.W.C. Lau

Christian Santangelo

We investigate the effect of counterion fluctuations in a single polyelectrolyte brush in the absence of added salt by systematically expanding the counterion free energy about Poisson-Boltzmann mean-field theory. We find that for strongly charged brushes, there is a collapse regime in which the brush height decreases with increasing charge on the polyelectrolyte chains. The transition to this collapsed regime is similar to the liquid-gas transition, which has a first-order line terminating at a critical point. We find that, for monovalent counterions, the transition is discontinuous in theta solvent, while for multivalent counterions, the transition is generally continuous. For collapsed …

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Distribution Of Counterions Near Discretely Charged Planes And Rods, M. L. Henle, Christian Santangelo, D. M. Patel, P. A. Pincus

Christian Santangelo

Realistic charged macromolecules are characterized by discrete (rather than homogeneous) charge distributions. We investigate the effects of surface charge discretization on the counterion distribution at the level of mean-field theory using a two-state model. Both planar and cylindrical geometries are considered; for the latter case, we compare our results to numerical solutions of the full Poisson-Boltzmann equation. We find that the discretization of the surface charge can cause enhanced localization of the counterions near the surface; for charged cylinders, counterion condensation can exceed Oosawa-Manning condensation.

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Structural And Computational Depth Of Diffusion Limited Aggregation, D. Tillberg, Jonathan Machta

Jonathan Machta

Diffusion-limited aggregation (DLA) is studied from the perspective of computational complexity. A parallel algorithm is exhibited that requires a number of steps that scales as the depth of the tree defined by the cluster. The existence of this algorithm suggests a connection between a fundamental computational and structural property of DLA.

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Long Distance Chiral Corrections In B Meson Amplitudes, Juan J. Sanz-Cillero, John Donoghue, Andreas Ross

John Donoghue

We discuss the chiral corrections to f_B and B_B with particular emphasis on determining the portion of the correction that arises from long distance physics. For very small pion and kaon masses all of the usual corrections are truly long distance, while for larger masses the long distance portion decreases. These chiral corrections have been used to extrapolate lattice calculations towards the physical region of lighter masses. We show in particular that the chiral extrapolation is better behaved if only the long distance portion of the correction is used.

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Precision Zeeman-Stark Spectroscopy Of The Metastable A(1)[Σ+3] State Of Pbo, David Kawall, F. Bay, S. Bickman, Y. Jiang, D. Demille

David Kawall

The metastable a(1)[Σ+3] state of PbO has been suggested as a suitable system in which to search for the electric dipole moment of the electron. We report here the development of experimental techniques allowing high-sensitivity measurements of Zeeman and Stark effects in this system, similar to those required for such a search. We observe Zeeman quantum beats in fluorescence from a vapor cell of PbO, with shot-noise limited extraction of the quantum beat frequencies, high counting rates, and long coherence times. We argue that improvement in sensitivity to the electron electric dipole moment by at least 2 orders of magnitude …

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The Nature Of Radio Continuum Emission In The Dwarf Starburst Galaxy Ngc 625, John M. Cannon, E. D. Skillman

John Cannon

No abstract provided.

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Hi Observations Of The Local Group Dwarf Wlm, D. Jackson, E. D. Skillman, John M. Cannon, S. Cote

John Cannon

No abstract provided.

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Low Temperature Silicon Epitaxy On Hydrogen Terminated Si(100) Surfaces, J. -Y. Ji, T. -C. Shen

T. -C. Shen

Si deposition on H terminated Si(001)-2×1 surfaces at temperatures 300–530K is studied by scanning tunneling microscopy. Hydrogen apparently hinders Si adatom diffusion and enhances surface roughening. The post-growth annealing effect is analyzed. Hydrogen is shown to remain on the growth front up to at least 10ML. Si deposition onto the H/Si(001)-3×1 surface at 530K suggests that dihydride units further suppress Si adatom diffusion and increase surface roughness.

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Global Dayside Ionospheric Uplift And Enhancements Due To Interplanetary Shock Electric Fields, B. R. Tsurutani, A. Mannucci, B. Ijima, A. Saito, K. Yumoto, M. A. Abdu, J. H.A. Sobral, W. D. Gonzalez, F. L. Guarnieri, T. Tsuda, Bela G. Fejer, T. J. Fuller-Rowell, J. U.O. Kozyra, J. C. Foster, A. Coster, V. M. Vasyliumas

Bela G. Fejer

[1] The interplanetary shock/electric field event of 5–6 November 2001 is analyzed using ACE interplanetary data. The consequential ionospheric effects are studied using GPS receiver data from the CHAMP and SAC-C satellites and altimeter data from the TOPEX/Poseidon satellite. Data from ∼100 ground-based GPS receivers as well as Brazilian Digisonde and Pacific sector magnetometer data are also used. The dawn-to-dusk interplanetary electric field was initially ∼33 mV/m just after the forward shock (IMF BZ = −48 nT) and later reached a peak value of ∼54 mV/m 1 hour and 40 min later (BZ = −78 nT). The electric field was …

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Rectification Of Thermal Fluctuations In Ideal Gases, Alejandro Garcia, P. Meurs, C. Van De Broeck

Alejandro Garcia

We calculate the systematic average speed of the adiabatic piston and a thermal Brownian motor, introduced by C. Van den Broeck, R. Kawai and P. Meurs [Phys. Rev. Lett. 93, 090601 (2004)], by an expansion of the Boltzmann equation and compare with the exact numerical solution.

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Synthesis, Crystal Structure And Thermoelectric Properties Of Β-K2bi8se13 Solid Solutions, Theodora Kyratsi, Duck-Young Chung, Jeff Dyck, Ctirad Uher, Sangeeta Lal, Sim Loo, Tim Hogan, John Ireland, Carl Kannewurf, Evripides Hatzikraniotis, Konstantinos Paraskevopoulos, Mercouri Kanatzidis

Jeffrey Dyck

Solid solution series of the type K2Bi8-xSbxSe13, K2-xRbxBi8Se13 as well as K2Bi8Se13-xSx were prepared and the distribution of the atoms (Bi/Sb, K/Rb and Se/S) on different crystallographic sites, the band gaps and their thermoelectric properties were studied. The distribution Se/S appears to be more uniform than the distribution of the Sb and Rb atoms in the β-K2Bi8Se13 structure that shows preference in specific sites in the lattice. Band gap is mainly affected by Sb and S substitution. Seebeck coefficient measurements showed n-type character for of all Se/S members. In the Bi/Sb series an enhancement of p-type character was observed. The …

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Quantum Mysteries Revisited Again, Padmanabhan Aravind

Padmanabhan K. Aravind

This paper describes a device, consisting of a central source and two widely separated detectors with six switch settings each, that provides a simple gedanken demonstration of the non-classical correlations that are the subject of Bell’s theorem without relying on either statistical effects or the occurrence of rare events. The mechanism underlying the operation of the device is revealed for readers with a knowledge of quantum mechanics.

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Microwave Thawing Of Cylinders., Tim Marchant

Tim Marchant

Microwave thawing of a cylinder is examined. The electromagnetic field is governed by Maxwell's equations, where the electrical conductivity and the thermal absorptivity are both assumed to depend on temperature. The forced heat equation governs the absorption and diffusion of heat where convective heating occurs at the surface of the cylinder, while the Stefan condition governs the position of the moving phase boundary. A semi-analytical model, which consists of ordinary differential equations, is developed using the Galerkin method. Semi-analytical solutions are found for the temperature, the electric-field amplitude in the cylinder and the position of the moving boundary. Two examples, …

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Deep Tissue Imaging Approaches By Direct Capture Of Two-Photon Absorptionmacro To Nano, T. Ye, W. Wagner, Peifang Tian, G. Yurtsever, M. Fischer, W. Wagner

Peifang Tian

No abstract provided.

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Asymptotic Solitons For A Third-Order Kortweg-De Vries Equation, Tim Marchant

Tim Marchant

Solitary wave interaction for a higher-order version of the Korteweg–de Vries (KdV) equation is considered. The equation is obtained by retaining third-order terms in the perturbation expansion, where for the KdV equation only first-order terms are retained. The third-order KdV equation can be asymptotically transformed to the KdV equation, if the third-order coefficients satisfy a certain algebraic relationship. The third-order two-soliton solution is derived using the transformation. The third-order phase shift corrections are found and it is shown that the collision is asymptotically elastic. The interaction of two third-order solitary waves is also considered numerically. Examples of an elastic and …

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Semi-Analytical Solutions For One - And Two-Dimensional Pellet Problems., Tim Marchant

Tim Marchant

The problem of heat and mass transfer within a porous catalytic pellet in which an irreversible first–order exothermic reaction occurs is a much–studied problem in chemical–reactor engineering. The system is described by two coupled reaction–diffusion equations for the temperature and the degree of reactant conversion. The Galerkin method is used to obtain a semi–analytical model for the pellet problem with both one– and two–dimensional slab geometries. This involves approximating the spatial structure of the temperature and reactant–conversion profiles in the pellet using trial functions. The semi–analytical model is obtained by averaging the governing partial differential equations. As the Arrhenius law …

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Alq3-Modified Indium Tin Oxide For Enhancing The Efficiency And Reliability Of Organic Light-Emitting Devices, Yf Liew, F.R. Zhu, Sj Chua, Jx Tang

Professor ZHU, Fu Rong

No abstract provided.

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Rapid Two-Dimensional Optical Spectroscopy Through Acousto-Optic Pulse Shaping, W. Wagner, Peifang Tian, L. Chunqiang, J. Semmlow, Warren Warren

Peifang Tian

No abstract provided.

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Cubic Autocatalysis With Michaelis - Menten Kinetics: Semi-Analytical Solutions For The Reaction - Diffusion Cell, Tim Marchant

Tim Marchant

Cubic-autocatalysis with Michaelis–Menten decay is considered in a one-dimensional reaction–diffusion cell. The boundaries of the reactor allow diffusion into the cell from external reservoirs, which contain fixed concentrations of the reactant and catalyst. The Galerkin method is used to obtain a semi-analytical model consisting of ordinary differential equations. This involves using trial functions to approximate the spatial structure of the reactant and autocatalyst concentrations in the reactor. The semi-analytical model is then obtained from the governing partial differential equations by averaging. The semi-analytical model allows steady-state concentration profiles and bifurcation diagrams to be obtained as the solution to sets of …

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Non-Contact Measurement Of Nerve Displacement During Action Potential With A Dual-Beam Low Coherence Interferometer, Christopher Fang-Yen, M Chu, H S. Seung, R R. Dasari, M S. Feld

Christopher Fang-Yen

No abstract provided.

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Science And Engineering Of Nanoparticle-Polymer Composites: Insights From Computer Simulation, Francis W. Starr, Sharon C. Glotzer

Francis Starr

No abstract provided.

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Spectral Densities Of Embedded Interfaces In Composite Materials, A. R. Mcgurn, Anthony Roy Day, D. J. Bergman, L. C. Davis, M. F. Thorpe

Anthony Roy Day

The effective resistivity and conductivity of two media that meet at a randomly rough interface are computed in the quasistatic limit. The results are presented in the spectral density representations of the Bergman-Milton formulation for the properties of two-component composite materials. The spectral densities are extracted from computer simulations of resistor networks in which the random interface separates two regions containing different types of resistors. In the limit that the bond lengths in the resistor network are small compared to parameters characterizing the surface roughness, the resistor network simulation approximates the continuum limit of the two-component composite. The Bergman-Milton formulation …

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Dynamic Heterogeneities In Supercooled Water, Nicolas Giovambattista, Marco Mazza, Sergey V. Buldyrev, Francis W. Starr, H. Eugene Stanley

Francis Starr

No abstract provided.

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Full-Text Articles in Physical Sciences and Mathematics

Particle Correlations At High Partonic Density, Kirill Tuchin

Kirill Tuchin

Qcd In Curved Space-Time: A Conformal Bag Model, Dmitri Kharzeev, Eugene Levin, Kirill Tuchin

Kirill Tuchin

Magnetospheric Electric Fields And Plasma Sheet Injections To Low-Lshells During The June 4-5, 1991 Magnetic Storm: Comparison Between The Rice Convectionmodel And Observations, T. W. Garner, R. A. Wolf, R. W. Spiro, W. J. Burke, Bela G. Fejer, S. Sazykin, J. L. Roeder, M. R. Hairston

Bela G. Fejer

Nanoscale Electronics Based On 2d Dopant Patterns In Silicon, T. -C. Shen, J. S. Kline, T. Schenkel, S. J. Robinson, J. -Y. Ji, C. L. Yang, R. R. Du, J. R. Tucker

T. -C. Shen

Effects Of Counterion Fluctuations In A Polyelectrolyte Brush, Christian Santangelo, A.W.C. Lau

Christian Santangelo

Distribution Of Counterions Near Discretely Charged Planes And Rods, M. L. Henle, Christian Santangelo, D. M. Patel, P. A. Pincus

Christian Santangelo

Structural And Computational Depth Of Diffusion Limited Aggregation, D. Tillberg, Jonathan Machta

Jonathan Machta

Long Distance Chiral Corrections In B Meson Amplitudes, Juan J. Sanz-Cillero, John Donoghue, Andreas Ross

John Donoghue

Precision Zeeman-Stark Spectroscopy Of The Metastable A(1)[Σ+3] State Of Pbo, David Kawall, F. Bay, S. Bickman, Y. Jiang, D. Demille

David Kawall

The Nature Of Radio Continuum Emission In The Dwarf Starburst Galaxy Ngc 625, John M. Cannon, E. D. Skillman

John Cannon

Hi Observations Of The Local Group Dwarf Wlm, D. Jackson, E. D. Skillman, John M. Cannon, S. Cote

John Cannon

Low Temperature Silicon Epitaxy On Hydrogen Terminated Si(100) Surfaces, J. -Y. Ji, T. -C. Shen

T. -C. Shen

Bela G. Fejer

Rectification Of Thermal Fluctuations In Ideal Gases, Alejandro Garcia, P. Meurs, C. Van De Broeck

Alejandro Garcia

Synthesis, Crystal Structure And Thermoelectric Properties Of Β-K2bi8se13 Solid Solutions, Theodora Kyratsi, Duck-Young Chung, Jeff Dyck, Ctirad Uher, Sangeeta Lal, Sim Loo, Tim Hogan, John Ireland, Carl Kannewurf, Evripides Hatzikraniotis, Konstantinos Paraskevopoulos, Mercouri Kanatzidis

Jeffrey Dyck

Quantum Mysteries Revisited Again, Padmanabhan Aravind

Padmanabhan K. Aravind

Microwave Thawing Of Cylinders., Tim Marchant

Tim Marchant

Deep Tissue Imaging Approaches By Direct Capture Of Two-Photon Absorptionmacro To Nano, T. Ye, W. Wagner, Peifang Tian, G. Yurtsever, M. Fischer, W. Wagner

Peifang Tian

Asymptotic Solitons For A Third-Order Kortweg-De Vries Equation, Tim Marchant

Tim Marchant

Semi-Analytical Solutions For One - And Two-Dimensional Pellet Problems., Tim Marchant

Tim Marchant

Alq3-Modified Indium Tin Oxide For Enhancing The Efficiency And Reliability Of Organic Light-Emitting Devices, Yf Liew, F.R. Zhu, Sj Chua, Jx Tang

Professor ZHU, Fu Rong

Rapid Two-Dimensional Optical Spectroscopy Through Acousto-Optic Pulse Shaping, W. Wagner, Peifang Tian, L. Chunqiang, J. Semmlow, Warren Warren

Peifang Tian

Cubic Autocatalysis With Michaelis - Menten Kinetics: Semi-Analytical Solutions For The Reaction - Diffusion Cell, Tim Marchant

Tim Marchant

Non-Contact Measurement Of Nerve Displacement During Action Potential With A Dual-Beam Low Coherence Interferometer, Christopher Fang-Yen, M Chu, H S. Seung, R R. Dasari, M S. Feld

Christopher Fang-Yen

Science And Engineering Of Nanoparticle-Polymer Composites: Insights From Computer Simulation, Francis W. Starr, Sharon C. Glotzer

Francis Starr

Spectral Densities Of Embedded Interfaces In Composite Materials, A. R. Mcgurn, Anthony Roy Day, D. J. Bergman, L. C. Davis, M. F. Thorpe

Anthony Roy Day

Dynamic Heterogeneities In Supercooled Water, Nicolas Giovambattista, Marco Mazza, Sergey V. Buldyrev, Francis W. Starr, H. Eugene Stanley

Francis Starr